Heating atoms

This is a simulator of Oxygen atoms. Do you know, where the wind comes from? The temperature difference between atoms create it! Atoms, that have higher temperature move up, but they also lose their heat. And the cooler atoms move down, but they gain heat. That's where the air movement comes from.

In this doodle, we have four different areas: two hot and two cold. Each atom wants to separate from other atoms, and at the same way to move up or down.